Background Increased iron stores are associated with greater cardiovascular risk in post-menopausal women. Oral contraceptive pill (OCP) use decreases the volume of menstrual blood loss and increases iron stores, but the link between OCP use, iron stores, and cardiovascular risk in pre-menopausal women has not been characterized. Study Design We conducted a cross-sectional study of 23 healthy OCP users to determine the association between type and duration of OCP exposure, iron stores, and vascular endothelial function [flow-mediated dilation (FMD) in the brachial artery]. Results Median duration of OCP use was 45 months. FMD in the brachial artery was significantly associated with progestin type used (estranes/gonanes vs. drospirenone) and duration of OCP use (both p<0.05) but not iron stores. In multivariate analysis, progestin type was the only independent predictor of FMD. Conclusions Use of OCP containing drospirenone was independently associated with greater FMD in the brachial artery, and thus a potentially more favorable cardiovascular risk profile, when compared with use of OCP containing estranes/gonanes.